Hi Sheldon,
You are correct, however, in your example configuration, the entire cookie value would need to remain static. Most times with JSESSIONID, I see customer's specifying where to look for the static portion of the cookie. For example, when servers return the JSESSIONID, part of the cookie will always be the same for the specific server, but the rest of it will change.
sticky 100 cookie JSESSIONID timeout 30
cookie offset 0 length 8
vserver VSERVER
virtual 10.10.10.1 tcp WWW
sticky 5 group 100
serverfarm REAL_SERVERS
persistent rebalance
inservice
The above example shows how to do it if you want to do sticky on the first 8 characters of the JSESSIONID cookie value. Another common set of values is:
cookie offset 53 length 10
Hope this helps.
Sean